Description: (E/Z)-Ensifentrine is a potent and selective PDE3/4 inhibitor. (E/Z)-Ensifentrine acts as a long-acting inhibitor of the phosphodiesterase enzymes PDE-3 and PDE-4, producing both bronchodilator and antiinflammatory effects. It is being developed by Verona Pharma as a potential treatment for asthma and hay fever, and is currently in clinical trials.